15 citations · 120 across the 17 of their papers we have counts for
17 papers
Quasiparticle Quality Factors in Superconducting Resonators: Effects of Bath Temperature and Readout Power
Zhenyuan Sun, S Withington, Songyuan Zhao
The performance of superconducting resonators underpins a wide range of modern quantum technologies, yet their quality factor often deviates at low temperatures from standard Matti…
Superconducting NbN Resonator Parametric Amplifiers for Millimetre Wavelengths
Songyuan Zhao, Stafford Withington, Christopher Thomas
We report the development of a reactive sputtering process for high NbN films with high normal-state resistivity, tailored for kinetic inductance parametric amplifie…
Superconducting Ring Resonators: Modelling, Simulation, and Experimental Characterisation
Zhenyuan Sun, Stafford Withington, Christopher Thomas +1
We present a theoretical and experimental study of superconducting ring resonators as an initial step toward their implementation in superconducting electronics and quantum technol…
Non-degenerate pumping of superconducting resonator parametric amplifier with evidence of phase-sensitive amplification
Songyuan Zhao, Stafford Withington, Christopher Thomas
Superconducting resonator parametric amplifiers are potentially important components for a wide variety of fundamental physics experiments and utilitarian applications. We propose…
Determining Absolute Neutrino Mass using Quantum Technologies
A. A. S. Amad, F. F. Deppisch, M. Fleck +19
Next generation tritium decay experiments to determine the absolute neutrino mass require high-precision measurements of -decay electron energies close to the kinematic end poin…
Superconducting resonator parametric amplifiers with intrinsic separation of pump and signal tones
Songyuan Zhao, Stafford Withington, Christopher Niall Thomas
Superconducting resonator parametric amplifiers achieve ultra-low-noise amplification through the nonlinear kinetic inductance of thin-film superconductors. One of the main challen…
Quantum Noise Limited Phased Arrays for Single-Electron Cyclotron Radiation Emission Spectroscopy
Stafford Withington, Christopher Thomas, Songyuan Zhao
Neutrino oscillation experiments show that neutrinos have mass; however, the absolute mass scale is exceedingly difficult to measure and is currently unknown. A promising approach…
Nonlinear characteristics of Ti, Nb, and NbN superconducting resonators for parametric amplifiers
Songyuan Zhao, Stafford Withington, Christopher Niall Thomas
Superconducting resonators and parametric amplifiers are important components in scientific systems such as kinetic inductance detector arrays, frequency-domain multiplexers for ot…
Effects of reactive, dissipative and rate-limited nonlinearity on the behaviour of superconducting resonator parametric amplifiers
Christopher N. Thomas, Stafford Withington, Songyuan Zhao
We present a formalism for modelling parametric amplification by resonators subject to rate-limited nonlinearity of mixed reactive/dissipative character, with particular relevance…
Nonlinear mechanisms in Al and Ti superconducting travelling-wave parametric amplifiers
Songyuan Zhao, Stafford Withington, Chris N. Thomas
The underlying nonlinear mechanisms behind the operation of travelling-wave parametric amplifiers (TWPAs) are important in determining their performance in terms of added noise, ma…
Quantum analysis of second-order effects in superconducting travelling-wave parametric amplifiers
Songyuan Zhao, Stafford Withington
We have performed a quantum mechanical analysis of travelling-wave parametric amplifiers (TWPAs) in order to investigate five experimental phenomena related to their operations, na…
Suppressed-gap millimetre wave kinetic inductance detectors using DC-bias current
Songyuan Zhao, Stafford Withington, David J. Goldie +1
In this study, we evaluate the suitability of using DC-biased aluminium resonators as low-frequency kinetic inductance detectors operating in the frequency range of 50 - 120 GHz. O…
Nonlinear Properties of Supercurrent-Carrying Single and Multi-Layer Thin-Film Superconductors
Songyuan Zhao, Stafford Withington, David J. Goldie +1
Superconducting thin-films are central to the operation of many kinds of quantum sensors and quantum computing devices: Kinetic Inductance Detectors (KIDs), Travelling-Wave Paramet…
Loss and Saturation in Superconducting Travelling-Wave Parametric Amplifiers
Songyuan Zhao, Stafford Withington, David J. Goldie +1
We have developed a coupled-mode analysis framework for superconducting travelling-wave parametric amplifiers using the full Telegrapher's equations to incorporate loss-related beh…
Calculation and measurement of critical temperature in thin superconducting multilayers
Songyuan Zhao, David J. Goldie, Chris N. Thomas +1
We have applied the Usadel equations to thin-film multilayer superconductors, and have calculated the critical temperature for general thin-film S-S' bilayer. We extended the bilay…
Electromagnetic models for multilayer superconducting transmission lines
Songyuan Zhao, Stafford Withington, David J. Goldie +1
Thin-film superconducting transmission lines play important roles in many signal transmission and detection systems, including qubit coupling and read-out schemes, electron spin re…
Exploring the performance of thin-film superconducting multilayers as Kinetic Inductance Detectors for low-frequency detection
Songyuan Zhao, David J. Goldie, Stafford Withington +1
We have solved numerically the diffusive Usadel equations that describe the spatially-varying superconducting proximity effect in Ti-Al thin-film bi- and trilayers with thickness v…